U.S. Pat. No. 4,082,686 relates to a liquid crystal based upon a Schiff Base that is known to be unstable and generally exhibit a mesomorphic range higher than about 45.degree. C. Similarly, U.S. Pat. No. 4,090,975 also utilizes a Schiff Base.
U.S. Pat. No. 4,202,791 relates to a nematic liquid crystal containing a cyclohexane ring therein, whereas U.S. Pat. No. 4,216,109 relates to a liquid crystal of a biphenyl type having a chlorine atom pendant to one of the phenyl groups.
U.S. Pat. No. 4,228,030 also relates to a liquid crystal material incorporating a cyclohexane ring therein, whereas U.S. Pat. No. 4,229,315 relates to liquid crystalline materials containing disubstituted cyclohexane groups.
However, none of these above patents teach a nematic liquid crystal having applicant's general formulation or good solubility.
German Offenlegungsschrift 2636684 generally relates to a cyclohexane-phenyl compound having alkyl groups or alkoxy groups substituted thereon. Japanese Pat. No. 57-49688 generally relates to a biphenyl group being substituted on each end thereof by a substituted cyclohexane.
U.S. Pat. No. 4,130,502 is a U.S. counterpart of the above German Publication 2636684.
U.S. Pat. No. 4,228,030 relates to various liquid crystal compositions generally containing substituted phenyl-cyclohexane compounds.
U.S. Pat. No. 4,330,426 also relates to liquid crystal compounds having a biphenyl-cyclohexane nucleus with the cyclohexane group and the phenyl group containing substituted alkyl groups thereon.
U.S. Pat. No. 4,331,552 relates to partially hydrogenated oligo-1,4-phenylenes which may be substituted.
U.S. Pat. No. 4,410,445 also relates to liquid crystal dielectrics containing phenyl or cyclohexyl rings in combination which may contain substituted groups thereon.
However, none of these patents relate to applicant's liquid crystal compound as disclosed herein.